The present invention relates to a fuel injection port of a fuel tank, and is suitable for vehicles.
In the prior art, for example, constitution of a fuel injection port 1 for automobiles is as shown in FIG. 1. The fuel injection port 1 is a cylindrical member projected from the right side wall of a fuel tank 3 towards the right-hand upper oblique direction. Numeral 5 in the figure designated a breather hose, numeral 6 designates a roll-over valve, and numeral 7 designates a canister. A fuel injection nozzle 9 is inserted in the fuel injection port 1 and a fuel 11 is injected into the tank 3.
As shown in FIG. 2, a fuel injection port 10 provided with a seal member (seal means) 14 in the inner circumferential surface is proposed (refer to SAE technical paper 851204). In FIG. 2, numeral 15 designates a retainer, and numeral 17 designates a trap door. In the fuel injection port 10, when the nozzle 9 is inserted, the trap door 17 is opened to the back side and the seal member 14 continues to the outer circumferential surface of the nozzle 9 in the circumferential direction and is closely contacted therewith (refer to FIG. 3). Thereby the air tightness is held within the tank 3 ever during the fuel injection.
In the fuel injection port 10 of FIG. 2, however, when the nozzle 9 is inserted, its top and portion (the surface usually having a number of flaws) interferes with the seal member 14 and may flaw this. In the flawed seal member 14, the air tightness of the tank is deteriorated and this state is not preferable.